Windshield wiper for motor vehicles

ABSTRACT

A windshield wiper for motor vehicles, having a support bracket ( 1 ) for connection to a wiper arm secured to a motor vehicle, wherein the support bracket ( 1 ) has an essentially U-shaped cross section and at least one support bracket detent recess ( 7 ); at least one lower bracket ( 2 ) for connection to a rubber wiper blade, wherein the lower bracket ( 2 ) has an essentially U-shaped cross section, has at least one lower bracket detent recess ( 11 ), and is at least partly embraced by the support bracket ( 1 ); and a joint ( 3 ) for pivotably connecting the at least one lower bracket ( 2 ) to the support bracket ( 1 ), wherein the joint ( 3 ) has a joint base body ( 12 ) at least partly embraced by the lower bracket ( 2 ), at least one lower bracket detent body ( 13 ), connected to the joint base body ( 12 ), for locking onto the at least one lower bracket detent recess ( 11 ), and at least one support bracket detent body ( 16 ), provided on the at least one lower bracket detent body ( 13 ), for locking onto the at least one support bracket detent recess ( 7 ).

[0001] The invention relates to a windshield wiper for motor vehicles.

[0002] In the prior art, numerous possibilities are known, in awindshield wiper, for pivotably connecting a support bracket, connectedto the wiper arm, to a lower bracket that carries a wiper blade. Most ofthese joints for connecting the lower bracket and the support bracketare complicated in structure and are unsuited to automated assembly.

[0003] The object of the invention is to refine a windshield wiper ofthe type defined above in such a way that a pivotable connection betweenthe support bracket and the lower bracket that can be assembled assimply as possible and is durable is created.

[0004] This object is attained by the characteristics of claim 1. Thenucleus of the invention is to provide the joint with a joint base body,which can be inserted from below into the lower bracket. The joint basebody is connected to a lower bracket detent body for locking onto thelower bracket. The lower bracket detent body furthermore has a supportbracket detent body for locking onto the support bracket.

[0005] According to claim 2, two lower bracket detent bodies areprovided. As a result, it is possible to fix the joint relative to thelower bracket.

[0006] According to claim 3, the two lower bracket detent bodies arepivotable elastically counter to one another. This makes assemblyeasier.

[0007] According to claim 5, the joint base body has an oval crosssection. This is a geometric shape that is especially easy to produce.

[0008] According to claim 7, the joint base body is embodiedcylindrically. This is a basic shape that is very easy to produce fromthe standpoint of production technology.

[0009] According to claim 8, the lower bracket detent body has a springslit. This makes it possible to compress the lower bracket detent body.

[0010] Additional characteristics and details of the invention willbecome apparent from the description of three exemplary embodiments inconjunction with the drawing. Shown are:

[0011]FIG. 1, an exploded view of a support bracket with a joint andlower bracket, in accordance with a first embodiment;

[0012]FIG. 2, an exploded view of a support bracket with a joint andlower bracket, in accordance with a second embodiment;

[0013]FIG. 3, a cross-sectional view taken along the section lineIII-III of FIG. 2; and

[0014]FIG. 4, an exploded view of a support bracket with a joint andlower bracket, in accordance with a third embodiment.

[0015] A first embodiment of the invention will be described below inconjunction with FIG. 1. A windshield wiper for a motor vehicle ispivotably connected to the free end of a wiper arm, which in turn isconnected to a motor vehicle. The windshield wiper has a central supportbracket 1, connected to the wiper arm; this support bracket is alsoknown as a middle bracket. In the region of the two free ends of thesupport bracket 1, a respective lower bracket 2, also known as a clawbracket, is pivotably connected via a joint 3, which is made from POM orsome other suitable plastic. A rubber wiper blade or another lowerbracket 2 is secured to the free ends of the two lower brackets 2.

[0016] The support bracket 1, which is of metal, has a U-shaped crosssection open toward the bottom and is formed by a support bracket base 4and by two support bracket legs 5, 6 extending vertically downward fromthe edge of the base; the base 4 and the legs 5, 6 are embodiedintegrally with one another. A detent bore 7, embodied as a supportbracket detent recess, is provided in each of the legs 5, 6, and the twodetent bores 7 are opposite one another.

[0017] The metal lower bracket 2 likewise has a U-shaped cross sectionthat is open at the bottom, and it is formed by one lower bracket base 8and two lower bracket legs 9, 10 extending vertically downward from theedge of the base; the base 8 and the legs 9,10 are embodied integrallywith one another. An oblong slot 11, embodied as a lower bracket detentrecess, with an essentially rectangular cross section is provided ineach of the legs 9, 10; the orientation of its longitudinal length isessentially parallel to that of the lower bracket 2. The oblong slots 11provided in the legs 9, 10 are opposite one another. The support bracket1 is dimensioned such that it can partly embrace the lower bracket 2,with play.

[0018] The plastic joint 3 has an essentially U-shaped cross section,and the base of the U is called the joint base body 12. The joint basebody 12 is connected integrally to two detent arms 13, 14, embodied aslower bracket detent bodies, which extend essentially parallel to oneanother. The detent arms 13, 14 are pivotable elastically counter to oneanother. Each of the detent arms 13, 14 has one outward-protrudingdetent protrusion 15, extending from its respective free end toward thejoint base body 12; the detent protrusion is thicker than the remainingportion of the detent arms 13 or 14 and corresponds in contour to theshape of the oblong slot 11. In the vicinity of the free end of thedetent arm 13 and 14, a cylindrical detent peg 16 is provided,protruding outward relative to the detent protrusion 15 and embodied asa support bracket detent body; its diameter is slightly less than thediameter of the detent bore 7. Adjacent the detent peg 16 and between itand the joint base body 12, a longitudinal groove 17 is provided, whichextends substantially perpendicular to the longitudinal direction of thedetent arms 13, 14. Between the longitudinal groove 17 and the jointbase body 12, a guide rib 18 is provided on the detent protrusion 15,protruding relative to this detent protrusion. Two spring elements 20,21, associated with one another, are provided on the inside 19 of thedetent arms 13, 14. The spring elements 20, 21 each comprise one basestrip 22, protruding at an acute angle from the inside 19 and embodiedintegrally with the respective detent arm 13 or 14, and one cover strip23, also protruding at an acute angle from the inside 19 and embodiedintegrally with the respective detent arm 13 and 14; the cover striprests on the base strip 22 and protrudes past it. The cover strips 23are each joined by film hinges 24 to the detent arms 13, 14. Relative toa plane of symmetry extending through the joint base body 12, the joint3 is embodied mirror-symmetrically.

[0019] The assembly of the windshield wiper in the first embodiment willnow be described. For assembly, the two detent arms 13, 14 are pressedtogether in the direction of the arrows R and R′, counter to thecounterforce generated by the elasticity of the detent arms 13, 14 andby the compression of the spring elements 20 and 21. Next, the supportbracket 1 is slipped over the lower bracket 2, so that the detent bore 7is substantially in alignment with the end, shown on the left in FIG. 1,of the oblong slot 11. The unit comprising the support bracket 1 and thelower bracket 2 is slipped onto the joint 3 along the direction of thearrow V, until this joint is locked onto the support bracket 1 and thelower bracket 2. In this process, the detent protrusion 15 enters intoengagement with the oblong slot 11, and the detent peg 16 enters intoengagement with the detent bore 7. The lower bracket 2 is now pivotablyconnected to the support bracket 1 and is pivotable about the detent peg16; the possible range of pivoting is selected such that it is adaptedto the changes in curvature during wiping of a windshield or rear windowof a motor vehicle. The inside 25 of the legs 5, 6 slides along theguide ribs 18, which prevents the legs 5, 6 from sliding directly on thelegs 8, 9, which would cause metallic scraping noises. The advantage ofthe joint 3 is that the lower bracket 2 and support bracket 1, which areboth of metal, can be assembled simply, quickly and automatically, sinceall that has to be done is to lock the parts onto one another in detentfashion. It is especially advantageous that the joint 3 is embodiedmirror-symmetrically. In automated assembly, an otherwise complicatedorientation of the joint 3 is thus unnecessary, and as a result theautomated assembly can be speeded up greatly.

[0020] A second embodiment of the invention will now be described, inconjunction with FIGS. 2 and 3. Identical parts are assigned the samereference numerals as in the first embodiment. Structurally differentbut functionally identical parts are given the same reference numeralswith a prime. Otherwise, reference is made to the description of thefirst embodiment. The support bracket 1 has two opposed detent bores 7that have a circular cross section and a diameter DT. The lower bracket2 has two opposed receiving bores 26 with a circular cross section and adiameter D_(U); D_(U)>D_(T).

[0021] The plastic joint 3′ is embodied as a hollow-profile body with anessentially oval cross section. It has two opposed, parallel side walls27, 28, which are joined to one another via curved connecting walls 29,30. The walls 27, 28, 29 and 30 are embodied integrally with oneanother. The walls 27, 28 are elastically compressible. On the outsideof the walls 27, 28, a disk 31 embodied as a lower bracket detent bodyis provided in the middle; its diameter perpendicular to the pivot axis32 is slightly less than the diameter D_(U). The thickness of the disk31 is selected such that it is slightly greater than the thickness ofthe legs 9 or 10. It is also possible to provide the disk with anoncircular cross section, such as a rectangular cross section; in thatcase, the inside contours of the receiving bore 26 are shapedaccordingly as well. A nonround cross section has the advantage that thejoint 3′ is fixed relative to the lower bracket 2 in terms of pivotingmotions about the pivot axis 32. A cylindrical detent peg 16 embodied asa support bracket detent body is provided on the disk 31; its diameteris slightly less than the diameter DT. The joint 3′ is embodiedmirror-symmetrically with respect to a plane of symmetry 33 extendingperpendicular to the pivot axis 32. The joint 3′ is moreover symmetricalrelative to a rotation of 180° about the pivot axis 32.

[0022] For assembly, the two side walls 27, 28 are pressed togetheralong the arrows R and R′. Next, the support bracket 1 is slipped ontothe lower bracket 2, so that the detent bores 7 and the receiving bores26 come to coincide. Next, the pressed-together joint 3′ is insertedfrom below in the direction of the arrow V into the lower bracket 2,until the disks 31 lock onto the respective receiving bores 26, and thedetent pegs 16 lock onto to the detent bores 7. The lower bracket 2 isnow pivotable about the pivot axis 32 relative to the support bracket 1.The advantages in automated assembly described in conjunction with theexemplary embodiment apply equally here.

[0023] A third embodiment of the invention will now be described inconjunction with FIG. 4. Identical parts are assigned the same referencenumerals as in the first embodiment. Parts that are different butfunctionally identical are given the same reference numerals with doubleprimes. Otherwise, reference is made to the description of the firstexemplary embodiment. The joint 3″ essentially takes the shape of acylindrical pin. The joint 3″ has a cylindrical joint base body 12″ aswell as a cylindrical detent neck 34, one provided on each of the twoface ends, which is embodied as a lower bracket detent body and has adiameter that is slightly less than the diameter of the joint base body12″. On the outer face ends of the detent necks 34, guide rings 35 areprovided, whose diameter is greater than that of the detent necks 34 butless than that of the joint base body 12″. One cylindrical detent peg16″ is provided on the outer face end of each of the guide rings 35; thediameter of each detent peg is essentially equivalent to that of thedetent necks 34. The detent necks 34 and the detent pegs 16″ have springslits 36 that divide them in half. The joint base body 12″, the detentnecks 34, the guide rings 35, and the detent pegs 16″ are embodiedintegrally. Relative to a plane of symmetry passing through the basebody 12″ perpendicular to the pivot axis 32, the joint 3″ is embodiedmirror-symmetrically. Furthermore, the outer contour of the joint doesnot vary in response to rotations about the pivot axis 32.

[0024] The support bracket 1 has opposed support bracket detent recesses37, which are disposed in the legs 5, 6 and take the form of a keyholeopen at the bottom. In the legs 9 and 10, the lower bracket 2 has twoopposed lower bracket detent recesses 38, which likewise take the shapeof a keyhole open at the bottom. A base body recess 39 of essentiallyrectangular cross section is provided in the base 8 between the detentrecesses 38.

[0025] For assembly, the lower bracket 2 is slipped onto the joint 3″,in the course of which the detent necks 34 lock onto the lower bracketdetent recesses 38. By means of the spring slits 36, the detent necksare elastically compressible to a certain extent, so that it is possibleto slide them through the narrowest point of the keyhole-shaped detentrecess 38. Next, the support bracket 1, partly embracing the lowerbracket 2, is slipped onto the detent pegs 16″, causing the latter toenter into the detent engagement with the detent recesses 37. The springslits 36 perform the same function here. Fixation of the joint 3″ alongthe pivot axis 32 is attained by providing that the base body 12″ isthrust partway through the base body recess 39, which in terms of itswidth is adapted to the width of the joint body 12″. The guide rings 35assure that the support bracket 1 is pivotable, at a predeterminedspacing from the lower bracket 2, about the pivot axis 32, so thatfriction does not occur between the legs 5 and 9 on the one hand and 6and 10 on the other. With respect to the advantages of assembly, see thedescription of the first exemplary embodiment.

1. A windshield wiper for motor vehicles, having a) a support bracket(1) for connection to a wiper arm secured to a motor vehicle, whereinthe support bracket (1) has i) an essentially U-shaped cross section andii) at least one support bracket detent recess (7; 37); b) at least onelower bracket (2) for connection to a rubber wiper blade, wherein thelower bracket (2) i) has an essentially U-shaped cross section, ii) hasat least one lower bracket detent recess (11; 26; 38), and iii) is atleast partly embraced by the support bracket (1); and c) a joint (3; 3′;3″) for pivotably connecting the at least one lower bracket (2) to thesupport bracket (1), wherein the joint (3; 3′; 3″) has i) a joint basebody (12; 12′; 12″) at least partly embraced by the lower bracket (2),ii) at least one lower bracket detent body (13, 14; 31; 34), connectedto the joint base body (12; 12′; 12″), for locking onto the at least onelower bracket detent recess (11; 26; 38), and iii) at least one supportbracket detent body (16, 16″), provided on the at least one lowerbracket detent body (13, 14; 31; 34), for locking onto the at least onesupport bracket detent recess (7; 37).
 2. The windshield wiper of claim1, characterized in that two lower bracket detent bodies (13, 14; 31;34) are provided.
 3. The windshield wiper of claim 2, characterized inthat the two lower bracket detent bodies (13, 14; 31; 34) are pivotablyelastically counter to one another.
 4. The windshield wiper of claim 1or 2, characterized in that the joint (3) has an essentially U-shapedcross section with two detent arms (13, 14), which are connected to thejoint base body (12).
 5. The windshield wiper of claim 1 or 2,characterized in that the joint base body (12′) has an oval crosssection.
 6. The windshield wiper of claim 5, characterized in that thelower bracket detent bodies (31′) are embodied cylindrically.
 7. Thewindshield wiper of claim 1 or 2, characterized in that the joint basebody (12″) is embodied cylindrically.
 8. The windshield wiper of claim7, characterized in that the lower bracket detent bodies (34) have aspring slit (36).
 9. The windshield wiper of one of the foregoingclaims, characterized in that the at least support bracket detent body(16; 16″) has an essentially circular cross section.
 10. The windshieldwiper of claim 9, characterized in that the support bracket detent body(16″) has a spring slit (36).